Torsion pre-load means



April 4, 1967 R. J. BOEDIGHEIMER 3,312,420

TORS ION PRE-LOAD MEANS Original Filed Jan. 2, 1964 United States Patent9 Claims. (Cl. 242-10111 This is a continuation of application Ser. No.335,026, filed I an. 2, 1964, and now abandoned.

This invention relates to torsion pre-load means for a safety seat beltretractor device and in particular to a torsion pre-load means for thespring winding mechanism of a seat belt retractor device that allowsvehicle seat belt lengths to be rolled up by a retractor or roll-up typedevice into spiral coils that are thereby kept in a compact condition inorder to prevent their being soiled or otherwise being caught inundesirable areas of the vehicle where they could be damaged.

It is therefore a general object of this invention to provide a torsionpre-load means for a retractor or belt roll-up device for vehicle safetybelts.

Another object of this invention is to provide a spring pre-windingmeans for the coil spring of a belt retractor device used to roll up thevehicle safety seat belt into a compact unit which would otherwise besoiled or dam-aged by coming in contact with objects or other portionsof the vehicle.

Another object of this invention is to provide a torsion pre-loadingdevice that limits the movement of the relatively rotational componentsof a safety seat belt retractor device .to permit easy and safeinstallation of the retractor device on the vehicle safety belt.

Still another object of this invention is to provide a spring pre-windmechanism for a seat belt retractor which measures the degree ofpre-loading and which counts each revolution of the reaction member ofthe retractor device relative to the spring container by issuing anaudible click for each revolution.

A still further object of this invention is to provide a pre-wind clipmeans fastenable to the safety seat belt retractor device for allowing360 degree turn of pre-loading of the retractor spring but preventingany unloading or unwinding of the retractor spring.

Another object of this invention is to provide a prewind clip means fora safety seat belt retractor device that may readily be attached to theretractor device or readily removed therefrom for disposal or for otherpurposes.

The foregoing and other objects and advantages of the present inventionbecomes apparent in the following detailed description thereof when readin conjunction with the accompanying drawings:

FIG. 1 is perspective view of a seat equipped with safety seat beltshaving a retractor or roll up device attached thereto;

FIG. 2 is a view taken along line 22 of FIG. 1;

FIG. 3 is a longitudinal view of the pre-wind retainer means on the beltretractor mechanism taken along line 3-3 of FIG. 4;

FIG. 4 is a sectional view taken along line 4-4 of FIG. 3;

FIG. 5 is a view taken along line 5-5 of FIG. 4;

FIG. 6 is a view taken along line 6-6 of FIG. 5; and

FIG. 7 is an exploded view of the invention.

With reference now to the figures there is shown a vehicle seat 1 uponwhich rests a safety seat belt structure 2 having seat belt lengths 3, 3each attached to a vehicle anchor end 4 and each at the forward endhaving a coupling member 5. A safety seat belt take-up 3,312,420Patented Apr. 4, 1967 means in the form of a retractor or roll-up device7 is fastened to each seat belt length 3 and comprises an energy storingmeans which may take the form of a barrelshaped or tubular member 9, areaction means in the form of a generally U-shaped bail or arm or levermeans 10 relatively rotati-vely journalled with respect to the member 9,and a spring means in the form of a helical coil spring 11 in the member9. Each belt length 3 is disposed about the barrel in double spiral beltlayers or coils as seen in FIGS. 1 and 2.

The tubular member 9 has an elongated slot 12 extending longitudinallythereacross and a clamp means 13 opposite the side of the barrel slot12. The clamp means 13 include a pair of generally L-shaped arms 14, 14as viewed in FIG. 4, attached through the barrel above slots 15, 15formed from punching out the arms from the tube 9. The reaction member10' includes a transverse or axially extending arm 16 and a pair ofradial arms 17, 18. Radial arm 17 has a U-shaped free end portion 19having an extension 20 received in an opening or recess 21 of the driverplug 22 received into one end 22a of the barrel 9 and the other radialarm 18 has an end part 23 extending into the aperture or recess 24 inthe anchor plug 25. The anchor plug 25 is constrained for rotationrelative to the tubular member 9 by being looked to the latter. Theanchor plug 25 on its outside periphery is provided with an aperture orrecess 28 and it has its disc portion 29 against the barrel edgeretaining it against inward axial movement and intermediate guideportion 30 and a shaft portion 31 extending inwardly into the barrel 9and having an elongated axially extending slot 32. The inner end of theanchor shaft portion 31 has a reduced tip portion 33 and theconvolutions of the helical spring 11 extend about .the shaft portion 31with a spring end extension 34 extending into the shaft 32 and slidabletherealong. The inner tip portion 33 of the shaft portion 31 is receivedinto the counter bore 35 of the spring hub 'drive shaft portion 36 whichhas an elongated axial slot 38 forreceiving .the other tip end 39 of thespring 11 which is slidable therein and along. The spring driver member22 has an enlarged guide portion 40 connecting with the shaft portion361 and a disc or flange 41 which engages the side of the tubular member9 to limit inward axial movement thereof.

The torsion pre-load means comprises a pre-wind retainer clip 42 and cammeans in the form of a cam and ratchet tooth part 44 of thespring-driver hub portion 40 of the member 22 as referred to FIGS. 3through 7. The cam means of the driver hub portion 40 has a camperiphery or surface 44 having an outer arcuate orcircular peripheralsurface section 44a joining a flat surface section 44b that connectswith flat surface section 44b perpendicular to surface section 44c. Thesurface sections 44b and 440 define a ratchet tooth zone with thesurface section 44a 'and the surface section 44b. The surface section44b merges to section 44a to define a cam zone. The pre-wind clip whichmay be removed from or placed on the retractor device 7 comprises aresilient strip of material which may be made from spring steel. Thisstrip is arcuate in shape and is defined by interconnected curved fingerportions 46 and 47 which are clasped about the outer periphery of thetubular member 9. Each of the finger portions 46 and 47 have tabs ortransversely extending flanges 48 and 49 respectively at their free endsfor snapping in and removing the clip from the retractor mechanism 7. Acurved spring lead or arm 50 extends from the finger portion 46 anddefines with the finger portions 46, 47 and the interconnecting portion45 an L-shaped groove 52, the spring leaf 50 at its free end having aprojection 53 extending radially inward through an enlarged slot 54 atthe end of the tubular member 9 and connecting with the slot 12, theprojection 53 further extending radially inward and engaging with thefiat surface section 44c as seen in FIG. 5.

Operation The retractor mechanism 7 is placed in a prewound conditionprior to its installation on the vehicle seat belt length. This isaccomplished by rotating the tubular member 9 while holding the reactionmember 10 fixed. The direction of rotation may be indicated on theexterior of the barrel as shown in FIG. 6. The winding of the spring 11may be mechanical, as the number of revolutions increase the barrelbecomes harder to wind and hold relative to the reaction member 10 andif set free could hurt the hands of the user.

In order to avoid such and similar difliculties the prewind clip 42being of flexible spring-like material, is placed around and slipped onthe barrel 9 with the projection 53 entering the slot 54 in the barrel 9and register ing with the flat cam surface 440 i.e. to permit theoutside vertical surface of the projection to engage with the vericalsurface of the ratchet tooth portion. Then by rotating the barrel in thedirection of the arrow with the reaction member fixed, the projection 53is allowed to have its lower tip end slide along the cam surface 44buntil the outer peripheral surface 44a of the cam 44 is reached whencethe projection 53 rises and rides on the outer periphery 44a forapproximately one revolution of the barrel 9 and then rides over thetooth edge (see dotted line position, FIG. and on to the cam surface44!) making an audible click. The procedure is repeated until sufficientnumber of revolutions are made to place the retractor device in thedesired pre-Wound or loaded condition. By counting the number of audibleclicks or revolutions one may determine the extent ofspring loadingwhich is directly related to the length of a seat belt portion to berolled. The projection 53 engaging with the radial stop surface 44cprevents movement of the barrel9 relative to the reaction member in theopposite direction of winding (i.e. in a direction opposite to thedirection the arrow is pointing). The retractor mechanism 7 is thenfastened to the belt by the clamp means 13 and the pre-wind clip 42 isthen removed and the belt sections 3, 3 are allowed to wind about theretractor mechanism 7 in a double-ply spiral coils. The pre-wind clip 42may be then discarded or used at a later time should it be desired toput the retractor device 42 on another seat belt. It will be noted thatthe hole 28 in the side of the anchor member may have a pin or otherelement inserted into it to hold the retractor mechanism in a pre-loadedcondition by having the edge of the pin en-' gage the retractor arm 18.This facilitates removal of the clip 42 prior to placing the mechanism 7on the safety seat belt.

Once the safety belt length is wrapped about the barrel of the retractordevice it is stored out of the Way from being soiled or damaged,

It will be appreciated that other variations and modifications of thisinvention may be made without departing from the spirit and scope of theappended claims wherein it is claimed:

1. In a retractor mechanism for rolling up a section of flat beltincluding a reel adapted for connection to a bight portion of said belt,a reaction member mounted for rotation with respect to said reel havinga portion thereof spaced from the axis of said reel adapted to bear onsaid belt, and a torsion spring having one end thereof anchored to saidreel and having the other end thereof adapted for connection to saidreaction member, the improvement comprising: drive means connectedbetween said reaction member and said other end of said spring, saiddrive means being provided with a cam surface and a stop surface; andclamp means disposed about said reel d and fastened against relativerotation with respect thereto, said clamp means including a stop elementhaving sliding engagement with said cam surface permitting winding ofsaid spring in one direction, said stop element being engageable withsaid stop surface in the other direction preventing unwinding of saidspring.

2. The structure according to claim 1 in which said clamp means is aresilient clip having end portions thereof disposed about said reel andin which said stop element is a radial projection extending inwardlyfrom said clip.

3. The structure according to claim 2 in which said cam surface isdisposed radially inwardly of said projection and in which said stopsurface is circumferentially disposed with respect to said projection inmovement obstructing relation thereto.

4. The structure according 0t claim 2 in which said projection comprisesa resilient arm cooperating with said cam surface and stop surface toproduce an audible click as said drive means is rotated with respect tosaid reel.

5. The structure according to claim 1 in which said drive means isrecessed within said reel, said reel including a slot registrable withsaid cam surface and stop surface, said stop element extending throughsaid slot into engagement with said cam surface, said stop element andstop surface co-acting with said reel to prevent rotation of saidreaction member relative to said reel in one direction while maintainingsaid spring in a wound state.

6. The structure according to claim 5 in which said clamp means is anarcuate shaped resilient clip having end portions thereof disposed ingripping relation with said reel, and in which said stop element isconnected to said end portions having a portion thereof extendingradially inwardly through said slot into engagement with said camsurface.

7. The structure according to claim 6 in which said stop surface isradially disposed and in which said cam surface has a graduallyincreasing radius, said stop element being adapted for radially inwardand outward movement with respect to said drive means permittingrelative rotation between said drive means and reel in one direction forwinding said spring.

8. The structure according to claim 6 in which said clip includes a pairof oppositely extending resilient fingers for gripping said reel havinga flexible projection extending radially inwardly between said fingersforming said stop element.

9. The structure according to claim 8 in which said clip comprises apair of interconnected arcuate finger portions of expandable resilientspring-like material, defining an aperture between the distal endsthereof each of said finger portions including a manual clasp tabproximate the distal end thereof for placing and removing said clip onand fro-m said reel.

References Cited by the Examiner UNITED STATES PATENTS 422,591 3/1890Hayden et al. 242107.11 1,070,684 8/1913 Harter 242--107.22

References Cited by the Applicant UNITED STATES PATENTS 1,313,644 8/l9l9Simon.

2,037,324 4/ 1936 Heusinkveld et al. 2,201,610 5/1940 Dawson. 2,684,0707/1954 Kelsey.

2,767,426 10/1956 Grupp.

2,830,655 4/1958 Lalande. 2,843,335 7/1958 Hoven et al. 2,945,275 7/1960.Almeter. 3,068,980 12/1962 Smirl.

FRANK J. COHEN, Primary Examiner.

1. IN A RETRACTOR MECHANISM FOR ROLLING UP A SECTION OF FLAT BELTINCLUDING A REEL ADAPTED FOR CONNECTION TO A BIGHT PORTION OF SAID BELT,A REACTION MEMBER MOUNTED FOR ROTATION WITH RESPECT TO SAID REEL HAVINGA PORTION THEREOF SPACED FROM THE AXIS OF SAID REEL ADAPTED TO BEAR ONSAID BELT, AND A TORSION SPRING HAVING ONE END THEREOF ANCHORED TO SAIDREEL AND HAVING THE OTHER END THEREOF ADAPTED FOR CONNECTION TO SAIDREACTION MEMBER, THE IMPROVEMENT COMPRISING: DRIVE MEANS CONNECTEDBETWEEN SAID REACTION MEMBER AND SAID OTHER END OF SAID SPRING, SAIDDRIVE MEANS BEING PROVIDED WITH A CAM SURFACE AND A STOP SURFACE; ANDCLAMP MEANS DISPOSED ABOUT SAID REEL AND FASTENED AGAINST RELATIVEROTATION WITH RESPECT THERETO, SAID CLAMP MEANS INCLUDING A STOP ELEMENTHAVING SLIDING ENGAGEMENT WITH SAID CAM SURFACE PERMITTING WINDING OFSAID SPRING IN ONE DIRECTION, SAID STOP ELEMENT BEING ENGAGEABLE WITHSAID STOP SURFACE IN THE OTHER DIRECTION PREVENTING UNWINDING OF SAIDSPRING.